Improvement in preparing, finishing, and polishing the surfaces of artificial stone



UNITED STATES PATENT OFFICE.

JOHN A. MEHLING, OF CLEVELAND, OHIO, ASSIGNOR OF ONE-THIRD HIS RIGHT TOJOHN W. HEISLEY, OF SAME PLACE.

IMPROVEMENT IN PREPARING, FINISHING, AND POLISHING THE SURFACES 0FARTIFICIAL STONE.

Specification forming part of Letters Patent No. 208,532, dated October1, 187 application filed July 26, 1878.

To all whom it may concern:

Be it known that I, JOHN A. MEHLING, of Cleveland, county of Ouyahoga,and State of Ohio, have invented certain new and useful Improvements inPreparing, Finishing, and Polishing the Surface of Artificial Stone, ofwhich the following is a full, clear, and exact description.

My invention has special relation to the finishing and polishing ofartificial stones.

Numerous experiments by me made indicate that this class of stones areextremely liable to be roughened by any hitherto-known means ofpolishing them or other stones, and that the production of ahighly-polished surface thereon, giving an appearance equal to the bestItalian, verd-antique, and similar marbles, has heretofore beenimpossible. To produce the desired finish and polish, thereby fittingthe artificial stone to take the place of the more expensive naturalmaterial in the decorative and other arts, is the object of myinvention; and to accomplish this the invention consists in certainprocesses or manipulations, which will be hereinafter first fullydescribed, and then pointed out in the claims.

The stone to be operated upon is colored as may be required (whenever itis not desired to be pure white) by pigments, like Indian red,VEI'IDIIIOH, Venetian red, ivory-black, lampblack, ultramarine orPrussian blue, ocher, paris-green, &c. The colors are mixed with thecomposition in accordance with formulae of my own, (not necessary to beherein detailed, since the proportions of ingredients are no essentialpart of the present invention,) and the mass is so manipulated as todraw the colors through it, giving the appearance of variegated marbleor of any suitably-colored stone. It is then rolled, spread, or moldedinto the desired form or shape, and permitted to dry until hard enoughto withstand the finishing process.

The cement and the intermingled pigments being of different degrees ofhardness and of different degrees of solubility in the liquidsordinarily employed in polishing, the mass presents a surface which itis extremely diflicult to reduce to the required finish. To overcomethese difficul ties, and to effectually ac complish the objects of theinvention, I proceed substantially as follows:

I first bring the mass to the desired level by rubbing it first withsandstone and then with coarse grit, following this with pumicestone, ora finer quality of grit, and finally with hone. In this rubbing, watermust be used with the above-named materials, for with dry stones or gritthe surface of the mass would be too much disturbed. When the stone hasbeen rubbed down to a level numerous pores and interstices will beapparent in the surface. The surface having thus been ground downsufficiently, in order to prepare it for the rubbing or polishing yet tobe described, an application of the material of which the stone iscomposed and water mixed therewith to the consistency of butter is madeto the ground surface, in order to fill up the pores and intersticesproduced by the grinding process. This will evidently afiord a surfaceof uniform hardness and solubility of its particles. The article is nowallowed to dry again, and when completely dry it is rubbed with honesteeped in oil (linseed or other oil capable of drying hard is used) orturpentine, or a mixture of oil and turpentine, until all theabove-described filling is apparently rubbed off-i. 6., until thesurface of the filling is brought down to a level with thepreviously-ground surface. It is then burnished with either blood-stone,agate, petrified wood, or steel, or other hard material suitable for aburnisher, all of which must be highly polished. In this part of theprocess, should water he used the rubbing would again disturb thesurface and open up the pores and interstices but by the use of the oiland turpentine, or their admixture, the burnishing instrument is keptfrom coming into too severe contact with the surface of the stone anddisturbin g it, and the oil and turpentine become, by the rubbing,incorporated with the particles forming the surface, and, as they dry,render it solid, compact, and tenacious enough to be susceptible of ahigh polish.

After the above burnishing, and after the surface is completely dry andhard, it is, in order to complete the smoothness of the surface,polished with a rag moistened with oil and any one of the followingpowders, viz: powdered chalk, giound rotten stone, Vienna whiting,French whiting, putty powder, powdered clay, tripoli, &c. After it ispolished as highly as possible with these materials, or any of them, Iagain rub the surface with bloodstone, agate, petrified wood, steel, orother material suitable for a burnisher, all of which must be highlypolished in order to communicate the desired luster to the polishalready obtained.

Following out the several steps as herein indicated, 1 am enabled toproduce a mirrorlike surface upon the artificial stone, similar inappearance to that of the highly-polished granites, marbles, &c., whichhas heretofore been regarded as practically impossible.

The utility of the invention is snfficiently obvious to all acquaintedwith the arts of cutting and polishing stone and the relative values ofthe natural and artificial varieties. It is therefore regarded asunnecessary to attempt to specify herein any of the numerous uses towhich the polished article may be applied.

I desire to add, however, that I am well aware of numerous varieties ofartificial stone made with a base of Keenes and other cement, and havingcoloring-matters applied in difierent ways; and I am also aware thatnumerous processes have been adopted for polishing the surfaces thereof.1 do not, therefore, desire to be understood as laying any claim hereinto the composition forming the stone, to the mere polishing of thesurface thereof, nor yet to any particular one of the steps gereinexplained when considered separately;

Having thus fully described my invention,

what I do claim as new, and desire to secure by Letters Patent, is-- 1.As an improvement in the art of polishin g artificial stone, the methodor process herein explained for bringing the surface to a conditionsuitable for receiving the polish, the same consisting in grinding withsandstone, grit, and hone, using water as a lubricator, then filling thepores with a solution of a like material to that of the base, allowingthe filling to become hard, and next rubbing the prepared surface withhone, using therewith oil and turpentine, or either, as a lubricator,and permitting the incorporated lubricator to become dry and hard,substantially as and for the purposes set forth.

2. The herein-described method of polishing and finishing artificialstone, the same consisting, essentially, in grinding with sandstone,grit, and hone, using therewith water as a 1nbricator, filling the poreswith a solution of a like material to that of the base, drying thefilling, rubbing down with oil and turpentine, or either, and burnishingwith blood-stone, agate, petrified wood, steel. or other hard materialsuitable for a burnisher, again drying and rubbing the dried surfacewith a cloth, using therewith oil and polishing-powder, and finishingwith agate, polished steel, &c., all substantially as set forth.

In testimony that 1 claim the foregoing I have hereunto set my hand inthe presence of two witnesses.

JOHN A. MEHLING.

Witnesses:

A. MEHLING, E. M. HEISLEY.

